356 OHIO BIOLOGICAL SURVEY 



Habitat mostly in fresh water, a few species marine, and a 

 few parasitic. 



Length 6-500 microns. 



The order may be separated into three families as follows: 



(e) TABLES OF FAMILIES, GENERA AND SPECIES. 



TABLE OF FAMILIES. 



Ai Green chloroleucites and red stigma present . 1. Fam. Euglenidae 



A- Green chloroleucites and red stigma absent; forms 

 colorless. 

 Bi Form radial, usually free swimming, nourishment 



saprophytic 2. Fam. Astasiidae 



B- Form bilateral, movement usually creeping, nour- 

 ishment through solid particles taken into the 

 pharynx 3. Fam. Peranemidae 



1. Fam. EUGLENIDAE Stein 



Euglenidae Stein 



Form oval elongate radial, usually somewhat flattened, the 

 body twisted spirally, metabolic; protoplasm containing green 

 chloroleucites as well as paramylon granules ; periplast often 

 with spirally arranged punctuations ; cytopharynx present from 

 which arises one or rarely two flagella ; red stigma present ; repro- 

 duction as a rule through division during the encysted stage, the 

 cysts often being enclosed within a gelatinous envelope. 



The species are inhabitants of fresh water with the exception 

 of Trachelomonas and Eutreptia, which are also found in salt 

 water. 



The number of described species which may be recognized 

 is 127, distributed throughout the world. 



TABLE OF GENERA 



Ai Provided with a single flagellum. 



B' Free swimming, not attached by a stalk. 



C^ Not provided with a brownish protective 

 covering. 



D" Periplast elastic, forms metabolic; typi- 

 cally radial in structure . . 1. Gen. Euglena 

 D- Periplast firm, thickened, forms not 

 metabolic; radial or compressed in 

 structure. 



